Step 1 :\(Q_n = n \times e\) where \(n\) is the integer value and \(e = 1.60217663 \times 10^{-19} C\)
Step 2 :\(F = k \times \frac{q_1 \times q_2}{r^2}\) where \(k = 8.9875517923 \times 10^9 N m^2 C^{-2}\) and \(r = 1 m\)
Step 3 :\(F_{Q1Q2} = 1.66109582939903 \times 10^{-26} N\)
Step 4 :\(F_{Q2Q3} = 1.2919634228659123 \times 10^{-26} N\)
Step 5 :\(F_{Q3Q4} = 9.689725671494343 \times 10^{-27} N\)
Step 6 :\(F_{Q4Q5} = 6.92123262249596 \times 10^{-27} N\)
Step 7 :\(F_{Q5Q6} = 4.614155081663973 \times 10^{-27} N\)
Step 8 :\(F_{Q6Q7} = 2.7684930489983838 \times 10^{-27} N\)
Step 9 :\(F_{Q7Q8} = 1.3842465244991919 \times 10^{-27} N\)
Step 10 :\(F_{Q10Q1} = -0.0 N\)
Step 11 :\(F_{Q18Q1} = -1.66109582939903 \times 10^{-26} N\)
Step 12 :\(F_{Q20Q4} = -1.384246524499192 \times 10^{-26} N\)
Step 13 :\(F_{Q13Q14} = 2.7684930489983838 \times 10^{-27} N\)
Step 14 :\boxed{\begin{array}{l} F_{Q1Q2} = 1.66109582939903 \times 10^{-26} N \\ F_{Q2Q3} = 1.2919634228659123 \times 10^{-26} N \\ F_{Q3Q4} = 9.689725671494343 \times 10^{-27} N \\ F_{Q4Q5} = 6.92123262249596 \times 10^{-27} N \\ F_{Q5Q6} = 4.614155081663973 \times 10^{-27} N \\ F_{Q6Q7} = 2.7684930489983838 \times 10^{-27} N \\ F_{Q7Q8} = 1.3842465244991919 \times 10^{-27} N \\ F_{Q10Q1} = -0.0 N \\ F_{Q18Q1} = -1.66109582939903 \times 10^{-26} N \\ F_{Q20Q4} = -1.384246524499192 \times 10^{-26} N \\ F_{Q13Q14} = 2.7684930489983838 \times 10^{-27} N \end{array}}\)